Microstructural assessment of rare corneal dystrophies using real-time in vivo confocal microscopy

Purpose : To analyse and describe three cases of rare corneal dystrophy and highlight their in vivo microstructural features. Methods : Subject 1 was diagnosed with a posterior stromal fleck corneal dystrophy. Two of her three children were also affected. Subjects 2 and 3 exhibited an almost identical clinical appearance on biomicroscopic examination, such that both clinically were diagnosed as having pre‐Descemet’s dystrophies. All subjects underwent in vivo confocal microscopy and approximately 300 sequential digital images were obtained and analysed for each cornea. Results : In vivo confocal microscopy of subject 1 demonstrated an abnormal appearance of numerous large ovoid particles, measuring 50–70 μm in diameter in the mid and posterior stroma as well as smaller hyperreflective dot‐like intracellular deposits, of less than 1 μm diameter. Despite the near‐identical clinical appearance, subjects 2 and 3 could be clearly differentiated by in vivo confocal microscopy. Subject 2 exhibited small, irregular, optically dense particles, mainly in the anterior stroma, whereas subject 3 possessed classical involvement of the stroma immediately adjacent to Descemet’s membrane, with numerous regular, small, hyperreflective particles. Conclusions : The ability of in vivo confocal microscopy to localize and accurately measure various elements in different corneal layers may help to resolve whether abnormalities are intra‐ or extracellular, and aid clearer differentiation of rare corneal disorders.     

In vivo confocal laser-scanning microscopy to characterize wound repair in rabbit corneas after collagen cross-linking

Background: Collagen cross‐linking using the photosensitizer riboflavin combined with ultraviolet A light was developed to stiffen the cornea by increasing its mechanical and biochemical stability. Investigation of post‐treatment events, such as wound healing, is important to evaluate possible risks and to optimize treatment protocols. This in vivo confocal laser‐scanning microscopy study in rabbits was conducted to provide a quantitative and qualitative analysis of corneal wound repair over 16 weeks following collagen cross‐linking. Methods: Six New Zealand White rabbits underwent riboflavin/ultraviolet A cross‐linking. In vivo confocal laser‐scanning microscopy using a Heidelberg Retina Tomograph equipped with a Rostock Cornea Module was performed preoperatively and at 2, 4, 8, 12 and 16 weeks postoperatively. Results: From 2 weeks onwards the epithelium demonstrated no abnormalities. Evidence of inflammation was visualized in the intermediate, basal cells and Bowman's membrane. Nerve fibre regeneration was first noted at 12 weeks. Keratocyte activation and hyperreflective extracellular matrix were observed consistently, but by 16 weeks keratocyte activation was diminished, and extracellular matrix resumed normal reflectivity. Cell density in the posterior stroma and endothelium regained preoperative values by 4 weeks, although anterior stroma keratocyte cell density was still reduced by about 10% at 16 weeks. Conclusions: Complete qualitative and quantitative characterization of corneal wound repair was achieved by in vivo confocal laser‐scanning microscopy over 16 weeks following collagen cross‐linking in rabbits. In terms of assessing the ever‐increasing range of cross‐linking protocols, in vivo confocal laser‐scanning microscopy may contribute to minimizing the number of experimental animals, because multiple examinations of the same cases are possible over time.     

Dystrophia Helsinglandica – corneal morphology,topography and sensitivity in a hereditary corneal disease with recurrent erosive episodes

Purpose: The aim of this study was to describe the morphology, corneal topography and sensitivity in individuals with Dystrophia Helsinglandica. This autosomal dominant corneal disease is characterized by recurrent corneal erosive episodes and progressive subepithelial fibrosis not significantly affecting visual acuity. Methods: The corneas of nine affected and nine unaffected individuals were examined using slit‐lamp biomicroscopy, in vivo confocal microscopy (IVCM) and videokeratography. Corneal mechanical sensitivity was also measured using a non‐contact esthesiometer. Results: Slit‐lamp biomicroscopy revealed that the affected individuals represented different stages of corneal changes, from a nearly normal cornea to subepithelial fibrosis of the central cornea. Corneal changes in affected individuals did not significantly decrease the best spectacle‐corrected visual acuity. In vivo confocal microscopy detected morphological changes in the epithelium and stroma. Subepithelial opacity formation including altered keratocytes could be found in the anterior stroma in all affected eyes. With the exception of two eyes (one affected and one unaffected), all videokeratographies showed irregular astigmatism. Corneal sensitivity was significantly lower in affected individuals (p = 0.01). Age and corneal sensitivity showed no correlation. Conclusion: The main morphological findings in affected individuals were discrete and progressive subepithelial fibrosis, in the in vivo confocal microscope corresponding to optically dense extracellular matrix and activated keratocytes. Subbasal nerve morphology was changed in the affected family members who also showed a decreased corneal sensitivity. The findings are per se not specific to the disease. The changes probably reflect a healing response to erosive events on the corneal surface influenced by the genotype.     

Imaging posterior polymorphous corneal dystrophy by in vivo confocal microscopy

To identify features of posterior polymorphous dystrophy (PPMD) by in vivo confocal microscopy, the corneas of a female patient with PPMD were examined using slit‐lamp biomicroscopy and slit‐scanning in vivo confocal microscopy. Characteristic endothelial vesicular and band lesions were seen clinically and easily identified using in vivo confocal microscopy. However, endothelial pleomorphism, an increased density and reflectance of posterior stromal keratocytes, and prominence of corneal nerves were also delineated. In vivo confocal microscopy enhances clinicopathological diagnosis and follow up of corneal dystrophies with subtle clinical presentations, such as PPMD.     

Morphological and functional correlations in riboflavin UV A corneal collagen cross‐linking for keratoconus

Purpose: To investigate the correlations between corneal structural modifications assessed by in vivo corneal confocal microscopy with visual function [uncorrected visual acuity (UCVA), best spectacle‐corrected visual acuity (BSCVA)] and morphological data (corneal topography, pachymetry, elevation analysis) after riboflavin UV A corneal collagen cross‐linking (CXL) for the stabilization of progressive keratoconus. Methods: Forty‐four eyes with progressive keratoconus were enrolled in the Siena Eye Cross Study (prospective nonrandomized phase II open trial). All eyes underwent Riboflavin UV A CXL. Preoperative and postoperative evaluation comprised: UCVA, BSCVA, optical pachymetry (Visante OCT, Zeiss, Germany), corneal topography (CSO, Florence, Italy) and tomography (Orbscan IIz; B&L, Rochester, NY, USA) and in vivo confocal microscopy (Heidelberg Retina Tomograph II; Rostock, Heidelberg Gmbh, Germany). Examinations were performed preoperatively 6 months and one day before treatment and at 1, 3, 6 and 12 months of follow‐up. Results: In vivo corneal confocal microscopy showed time‐dependent postoperative epithelial and stromal modifications after cross‐linking. Epithelial thinning associated with stromal oedema and keratocytes apoptosis explained initial tendency towards slightly reduced VA and more glare one month postoperatively in 70% of eyes. Furthermore, a statistically not significant early worsening of topographic mean K values was observed. Orbscan II analysis significantly underestimated pachymetric values after treatment. Pachymetric underestimation was rectified by high‐resolution optical pachymetry provided by the Visante OCT system. After the third post‐CXL month, epithelial thickening, disappearance of oedema and new collagen compaction recorded by in vivo corneal confocal microscopy explained the improvements in visual performance during the follow‐up. Changes in stromal reflectivity and collagen compaction observed by in vivo confocal microscopy were associated with corneal flattening and reduction in anterior elevation values recorded by differential topographic analysis. Conclusion: Corneal structural changes assessed by in vivo corneal confocal microscopy demonstrated significant correlations with visual function (UCVA and BSCVA) and morphological (corneal topography, pachymetry, elevation analysis) findings recorded after riboflavin‐UV A‐induced CXL.     

Clinicopathological features of ocular cystinosis

A 31‐year‐old woman who presented with photophobia was found to have bilateral corneal and conjunctival crystal deposition. Ocular cystinosis was diagnosed upon observation of typical crystals and lack of systemic involvement. In vivo confocal microscopy confirmed crystal deposition of the corneas and conjunctivae bilaterally. Optical coherence tomography showed stromal hyper‐reflectivity due to crystals within the corneal stroma. Transmission electron microscopy of the conjunctiva demonstrated pathognomonic intralysosomal cystine crystals inside fibroblasts and macrophages. Clinicopathological characteristics of ocular cystinosis are well described by this exceptional case.     

圆锥角膜行去上皮角膜胶原交联术后角膜微结构的变化

目的：采用共焦显微镜观察进展期圆锥角膜行去上皮角膜胶原交联术后角膜微结构的变化。

方法：选取2016-02/2017-02于我院行上皮角膜胶原交联术治疗的进展期圆锥角膜患者11例15眼,分别于手术前后行共焦显微镜检查,观察角膜微结构变化。

结果：术后早期角膜上皮下神经纤维显著减少或消失; 角膜前基质呈蜂窝状,几乎无典型的角膜基质细胞,术后3mo基质细胞开始出现,术后12mo基质细胞数量几乎恢复到术前水平,但角膜上皮下神经仍稀疏,未达到术前水平; 术后后部角膜基质细胞和内皮细胞大小及形态未受影响。

结论：角膜胶原交联术后角膜微结构发生变化最明显的是上皮下神经纤维和前基质细胞,但随着随诊时间的延长,这种变化呈逐渐减弱趋势。     

Differential diagnosis of corneal oedema assisted by in vivo confocal microscopy

The purpose of this study was to demonstrate microstructural differences between clinically similar, but aetiologically different, cases of corneal oedema in four subjects. In vivo confocal microscopy highlighted oedema of the basal epithelium, prominent nerve–keratocyte interactions, and typical ‘epithelialization’ of the endothelium in a case of iridocorneal endothelial syndrome; however, a similar microstructural appearance was observed in a case of presumed herpetic disciform keratitis. The latter diagnosis was subsequently revised on this basis. Confocal examination of Fuchs’ endothelial dystrophy demonstrated oedema of the basal epithelium, prominent wing cells, anterior stromal alterations, fibrosis of Descemet’s membrane and a typical ‘strawberry’ appearance of the endothelium. In contrast, in vivo microstructural examination of bilateral keratoconus with hydrops confirmed oedema mainly involving the epithelium and anterior stroma. In vivo confocal microscopy allows the clinician to observe the living cornea at a microstructural level and to better diagnose and differentiate borderline or unusual cases of corneal oedema.     

Dystrophia Smolandiensis: a novel morphological picture of recurrent corneal erosions

Purpose: The aim of this study was to describe morphological changes in Dystrophia Smolandiensis, a corneal disease that is characterized by recurrent corneal erosive episodes and the formation of central corneal keloid‐like opacities in approximately half of those affected. Methods: The corneas of seven affected individuals were examined using in‐vivo confocal microscopy. Specimens of one primary corneal graft, one regraft and one biopsied keloid‐like region – all obtained from members of a large family with the disease – were re‐examined with a light microscope. Sections were stained with Congo red and analysed immunohistochemically for fibronectin and S100A4. Results: Light microscopic examination revealed epithelial hyperplasia, absence of Bowman’s layer and subepithelial fibrosis. Fibronectin was expressed in the area of subepithelial fibrosis, and the keratocytes in this area generally expressed S100A4. The biopsy specimen stained positive for Congo red, suggesting an amyloid deposit. In‐vivo confocal microscopy confirmed epithelial abnormalities, loss of Bowman’s layer and significant alterations of the subbasal nerve plexus in affected individuals. Conclusion: The morphological picture in Dystrophia Smolandiensis is novel for a condition dominated by recurrent corneal erosions at the clinical level. Although no single morphological feature unique to the disease could be found, the general morphological pattern of pathology (true keloid formation, absence of Bowman’s layer, subepithelial fibrosis and abnormal subbasal nerves) probably reflects a novel phenotypic expression of the healing response to recurrent erosion of the corneal epithelium. However, the pathogenesis of Dystrophia Smolandiensis remains to be elucidated fully.     

The clinical value of in vivo confocal microscopy for diagnosis of ocular surface squamous neoplasia

Purpose

To determine the reliability and efficiency of in vivo confocal microscopy for the diagnosis of ocular surface squamous neoplasia (OSSN).

Methods

A case series with five consecutive cases of OSSN were investigated retrospectively, of which the characteristics and subspecial types had been estimated by in vivo confocal microscopy before surgery. The structure and cellular features of OSSN were analyzed with other examinations, such as anterior-segment optical coherence tomography (AS-OCT), and confirmed by histopathological biopsy.

Results

The tumors revealed red gelatinous surfaces with vascular dilatation on the ocular surface of the conjunctival and corneal epithelium in anterior segment photography. Involvement of only corneal epithelium was observed by AS-OCT in three cases, whereas the Bowman''s layer and anterior stroma were also invaded in the other two cases. In vivo confocal microscopy showed cellular anisocytosis and enlarged nuclei with high nuclear to cytoplasmic ratio in three cases diagnosed as conjunctival intraepithelial neoplasia; moreover, nests were partially formed by isolated keratinized, binucleated, and actively mitotic dysmorphic epithelial cells in the other two cases diagnosed as carcinoma in situ and ocular surface squamous carcinoma (OSSC). The characteristics assessed from histopathological biopsy were similar to that revealed by in vivo confocal microscopy in all five cases.

Conclusion

In vivo confocal microscopy analysis of cytological characteristics of OSSN is a safe, relatively noninvasive, and effective diagnostic tool in detecting characteristics of OSSN before surgical resection. Although in vivo confocal microscopy cannot replace excisional biopsy for definitive diagnosis, it can be valuable for initial diagnosis and management of patients with OSSN.     

Conjunctival and corneal findings in bleb‐associated endophthalmitis: an in vivo confocal microscopy study

Purpose: To report the conjunctival and corneal findings in delayed onset glaucoma filtering bleb‐associated endophthalmitis (BAE), by using in vivo confocal microscopy (IVCM). Methods: This was an observational case series. Four eyes of four glaucomatous patients who previously underwent mytomicin C augmented filtering surgery and affected with delayed onset BAE, underwent IVCM of conjunctival bleb and cornea at diagnosis, after 2 and 8 weeks of therapy. The inflammatory status of the conjunctival epithelium and sub‐epithelium was microscopically investigated. Corneal epithelial cells, stromal and endothelial morphology were also evaluated. A group of eight patients with functioning conjunctival filtering bleb was used as control. Results: At diagnosis, a diffuse inflammatory cell infiltration within the conjunctival epithelium presenting evident microcysts was found; conversely, there were no such alterations in the sub‐epithelium. An evident stromal oedema, keratocytes activation and diffuse endothelial inflammatory precipitates were the major corneal hallmarks. After 2 weeks of therapy, besides a remarkable improvement of epithelial inflammation and an evident reduction in endothelial precipitates, dendritic cells appeared within conjunctival sub‐epithelium and corneal epithelium showed aspects of cellular disruption. After 8 weeks, the conjunctival and corneal features consistently improved, except for the endothelium which still presented high‐reflective residual precipitates. Conclusions: In vivo confocal microscopy proved valuable in the analysis of conjunctival bleb and cornea in patients affected with delayed onset BAE, permitting an evaluation of the course of the disease, the response to therapy and the modulation of dose regimen.     

共焦显微镜观察慢性角膜水肿患者角膜各层形态特点

目的：应用活体共焦显微镜(IVCM)观察慢性角膜水肿患者角膜各层形态特点。

方法：使用IVCM观察不同病因的慢性角膜水肿的患者21例21眼,并与5例拟行白内障手术患者的正常角膜进行对照。

结果：IVCM观察到所有慢性角膜水肿患者角膜上皮层均可见大泡,表现为黑色、圆形、边缘清晰。18眼(86%)上皮细胞出现高反射的无细胞结构的片状区域和瘢痕。12眼(57%)患者中央区角膜上皮下未发现神经纤维,9眼(43%)患者中央区角膜上皮下神经平均密度显著降低。所有患者Bowman膜(BZ)表现为明显的异常,除了瘢痕外,BZ呈分支的、细的、黑线状。13眼(62%)患者前基质表现为细颗粒或粗颗粒,且反光不同。所有患者角膜基质细胞密度降低。所有患者角膜内皮表现为正常六边形结构消失,细胞边界不清。对照组角膜正常未见上述改变。

结论：IVCM可以用来观察慢性角膜水肿角膜各层微观结构上的变化,包括上皮瘢痕形成、上皮下神经纤维及基质细胞的减少。随着角膜内皮移植术的日益普及,本研究支持IVCM在定量评估术前、术后角膜水肿的作用。     

Ultrastructural and in vivo confocal microscopic evaluation of interface after Descemet’s Stripping Endothelial Keratoplasty in rabbits

Purpose: To study healing at the donor–recipient interface after Descemet’s Stripping Endothelial Keratoplasty (DSEK) in rabbits by ultrastructural and in vivo confocal microscopic evaluation. Methods: The right eye of eight New Zealand White rabbits underwent DSEK. Postoperatively, each rabbit was subjected to routine slitlamp examination daily for 2 weeks and then weekly for 6 weeks. In vivo confocal microscopic evaluation was performed at 1, 2, 4 and 8 weeks. Two rabbits were randomly chosen at 1, 2, 4 and 8 weeks for transmission electron microscopic examination. Results: Interface haze decreased with each follow‐up visit. Activated keratocytes and associated cellular processes were evident throughout all the follow‐ups with in vivo confocal microscopy. Highly reflective particles were left at the interface until the end‐point of the study. Upon ultrastructural evaluation, increased rough‐surface endoplasmic reticulum in keratocytes, clefts, folds and retained Descemet’s membrane (DM) were found. Conclusion: Clefts lack of adherence at the interface and degenerated keratocyte may make up the highly reflective particles. In addition, retained DM does not appear to affect adhesion and very minimal healing is produced at the DM–stroma smooth interface, which permits better quality of vision in Descemet’s membrane endothelial keratoplasty.     

Corneal and conjunctival findings after mitomycin C application in pterygium surgery: an in‐vivo confocal microscopy study

Purpose: To perform a qualitative assessment of the topical side‐effects of mitomycin C on cornea after pterygium surgery. Methods: In‐vivo confocal microscopy (Heidelberg Retina Tomograph II in combination with the Rostock Cornea Module) was performed in 10 patients with unilateral primary pterygium. Mitomycin C 0.02% was applied topically to seven eyes for 5 min intraoperatively and twice daily for 5 days postoperatively. Three eyes underwent surgery without application of cytostatic agent. Patient follow‐up was 1 month. Results: After application of mitomycin C, complete epithelialization of the operated zone was found 2 weeks after surgery. In‐vivo confocal microscopy revealed signs of superficial punctate keratitis for 2 weeks in the central cornea only after application of mitomycin C. The presence of epithelial and stromal oedema in this group was noted for up to 2 weeks in the central cornea and for up to 4 weeks in the operated zone. In the control group, complete epithelialization was found after 1 week; there were no signs of oedema after 1 week in the central cornea or after 2 weeks in the operated zone. Leucocyte infiltration and increased Langerhans cell density were noted in both groups in the operated and central zones. Analysis of the conjunctiva revealed a decrease in goblet cell density following cytostatic application. Conclusion: Local application of mitomycin C delays corneal epithelialization, and prolongs postoperative epithelial and stromal oedema in both the centre and periphery. Moreover, signs of punctate keratitis were noted 2 weeks after surgery in central intact cornea. Nevertheless, in‐vivo confocal microscopy shows that these changes are reversible 4 weeks after application of mitomycin C 0.02%.     

Biomicroscopia confocal en 4 pacientes con distrofia corneal policromática

Introduction

Polychromatic corneal dystrophy is an unusual pre-descemet dystrophy, about which there are very few publications. The findings are presented in a case series of four patients with polychromatic corneal dystrophy, using a slit lamp, specular biomicroscopy, and confocal microcospy.

Konfokale In-vivo-Hornhautmikroskopie nach Keratoplastik

Background

Seven eyes with clear grafts after penetrating keratoplasty were examined with in vivo confocal corneal microscopy in 1999. Our aim was the confocal microscopic investigation of the subclinical changes in clear grafts after long-term follow-up.

Methods

The preoperative diagnoses were keratoconus (two), granular corneal dystrophy (two), pseudophakic bullous keratopathy due to ACL (two), and corneal ulcer (one). The epithelium, corneal nerves, keratocytes of the anterior and posterior stroma, and endothelium were evaluated with confocal microscopy.

Results

Mean density of basal epithelial cells was 3928±378 cells/mm² at 15 months and 3284±565 cells/mm² at 66 months postoperatively. At 15 months the keratocyte density was 750±113 cells/mm² in the anterior stroma and 601±98 cells/mm² in the posterior stroma, at 66 months 383±53 cells/mm² in the anterior stroma and 411±98 cells/mm² in the posterior stroma. Endothelial cell density decreased from 1719±576 cells/mm² (15 months) to 965±272 cells/mm² (66 months).

Conclusions

In the follow-up period a significant decrease of keratocyte and endothelial cell density was detectable with confocal microscopy. The clinical importance of our findings must be clarified with further examinations on more patients.     

Clinical in vivo confocal microscopy of the human cornea in health and disease

Confocal microscopy enables microstructural analysis of the in vivo cornea, allowing fresh insight into corneal microstructure in health, and in inherited and acquired corneal disease. This method of corneal examination is evolving in an exponential fashion, with rapid advances in technology being mirrored by rapid growth in both research and clinical applications. Whilst initially the evidence base for in vivo confocal microscopy consisted largely of small case studies, in recent years there has been a trend towards collecting quantitative data in an effort to better delineate between heath and disease. Confocal microscopy has been utilised clinically to aid in the diagnosis of infectious keratitis, in particular Acanthamoeba and fungal keratitis, and has also established a role in the diagnosis and phenotyping of corneal dystrophies. This article reviews in vivo confocal microscopy of the human cornea in health and disease and examines clinical and research applications of this new technology.     

In vivo confocal microscopic characteristics of crystalline keratopathy in patients with monoclonal gammopathy: Report of two cases

In this paper, we report two cases of a 62-year-old patient presented with blurred vision and a 45-year-old male diagnosed with multiple myeloma who was referred from the Department of Oncology. Slit-lamp examination, in vivo confocal microscopy (IVCM), systemic work-up and serum protein electrophoresis were obtained. In both patients, slit-lamp findings revealed bilateral diffuse subepithelial and anterior stromal crystals and IVCM showed highly reflective deposits in the corneal epithelium and stroma. The first patient was eventually diagnosed with monoclonal gammopathy of undetermined significance following bone marrow biopsy and systemic evaluation. Unusual corneal deposits may constitute the first sign of monoclonal gammopathies. IVCM may be helpful in showing the crystalline nature of the corneal deposits and guiding the clinician to the diagnosis of gammopathies. Both ophthalmologists and oncologists should be aware that corneal deposits may herald a life-threatening hematologic disease.     

Pulsed vs continuous light accelerated corneal collagen crosslinking: in vivo qualitative investigation by confocal microscopy and corneal OCT

Purpose

To assess qualitative corneal changes and penetration of pulsed and continuous light accelerated crosslinking by in vivo confocal microscopy and corneal OCT.

Methods

A total of 20 patients affected from progressive keratoconus were enrolled in the study. Ten eyes of 10 patients underwent an epithelium-off pulsed-light accelerated corneal collagen crosslinking (PL-ACXL) by the KXL UV-A source (Avedro Inc.) with 8 min (1 s on/1 s off) of UV-A exposure at 30 mW/cm² and energy dose of 7.2 J/cm²; 10 eyes of 10 patients underwent an epithelium-off continuous-light accelerated corneal collagen crosslinking (CL-ACXL) at 30 mW/cm² for 4 min. Riboflavin 0.1% dextran-free plus hydroxyl-propyl-methylcellulose solution (VibeX Rapid, Avedro Inc.) was used for a 10-min corneal soaking. Treated eyes were examined by in vivo scanning laser confocal analysis and spectral anterior segment OCT at 1, 3, and 6 months.

Results

Epithelial stratification and nerves regeneration improved in time, being complete at month 6 in both groups without endothelial damage. Keratocyte apoptosis in PL-ACXL was estimated at a mean depth of ∼200 μm, whereas an uneven demarcation line was detectable by confocal microscopy at a mean depth of 160 μm in CL-ACXL.

Conclusion

In vivo confocal microscopy and corneal OCT allowed a precise qualitative analysis of the cornea after epithelium-off PL-ACXL and CL-ACXL treatments. Apoptotic effect was higher in pulsed than in continuous light treatments, exceeding 200 μm in corneal stroma. According to different morphological data, the clinical efficacy of ACXL needs to be determined in a long-term follow-up and large cohort of patients.     

The significance of Vogt's striae in keratoconus as evaluated by in vivo confocal microscopy

Background: To evaluate the association of the presence, extent and width of Vogt's striae with other microstructural corneal alterations in keratoconus using in vivo confocal microscopy (IVCM). Methods: Sixty‐eight keratoconic corneas of 68 patients were evaluated with slit‐lamp examination (SLE), corneal topography and IVCM. For each eye, the presence, extent and width of alternating light and dark bands (Vogt's striae) observed using IVCM was recorded together with keratocyte and endothelial cell densities, stromal nerve thickness, subbasal nerve density and thickness. The refractive status and the mean and steepest corneal curvatures were noted. Results: Vogt's striae were present in 43 (63.2%) eyes on SLE and dark bands were present in 53 (77.9%) eyes on IVCM. Compared with patients without dark bands, patients with dark bands had significantly higher refractive errors in spherical equivalents (SE; ?8.15 ± 3.70 vs. ?5.18 ± 2.46 diopters [D], P = 0.007), higher astigmatic errors (?5.88 ± 2.69 vs. ?4.10 ± 1.84 D, P = 0.027), higher steepest corneal curvatures (54.33 ± 4.38 vs. 51.23 ± 3.72 D, P = 0.018), lower anterior stromal keratocyte densities (1106 ± 172 vs. 1222 ± 171 cells/mm², P = 0.022) and lower nerve fibre densities (18.74 ± 6.54 vs. 22.66 ± 6.47 nerves/mm², P = 0.054). Compared with patients in whom dark bands were confined to the posterior stroma, patients with dark bands extending into the anterior stroma had significantly higher refractive errors in SE (?11.17 ± 2.25 vs. ?6.34 ± 3.48 D, P < 0.001), higher astigmatic errors (?7.44 ± 2.56 vs. ?4.69 ± 2.22 D, P = 0.006) and wider bands (6.0 ± 2.1 vs. 9.6 ± 3.1 µm, P < 0.001). Conclusions: Vogt's striae appear to be more prevalent in keratoconic corneas than can be appreciated clinically. The presence of Vogt's striae may be associated with corneal topographic and microstructural changes.